首先,來(lái)個(gè)簡(jiǎn)單的,獲取本應(yīng)用的信息 :

//獲取 build.gradle 中的 versionName 和 versionCode
try {
      PackageInfo info = getPackageManager().getPackageInfo(getPackageName(), 0);
      String name = info.versionName;
      int code = info.versionCode;
    } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
    }

是不是很簡(jiǎn)單 !

獲取其他應(yīng)用的信息

//獲取已安裝應(yīng)用的列表
List<PackageInfo> packages = getPackageManager().getInstalledPackages(0);
        if (packages.size() > 0) {
            for (int i = 0; i < packages.size(); i++) {
                PackageInfo packageInfo = packages.get(i);
                String packageName = packageInfo.packageName;   //app包名
                String versionName = packageInfo.versionName;  //app的versionName
                int versionCode = packageInfo.versionCode;  //app的versionCode
                String appName = packageInfo.applicationInfo.loadLabel(getPackageManager()).toString(); //app名
                Drawable icon = packageInfo.applicationInfo.loadIcon(getPackageManager());  //app圖標(biāo)
                          
                if ((packageInfo.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) == 0) {  
                    //非系統(tǒng)應(yīng)用 
                } else {
                    //系統(tǒng)應(yīng)用
                }
            }
 }

判斷某應(yīng)用是否已安裝

private boolean checkHasInstalled(String packageName) {
        PackageInfo pi;
        try {
            pi = getPackageManager().getPackageInfo(packageName, 0);
        } catch (PackageManager.NameNotFoundException e) {
            return false;
        }
        return pi != null;
    }